Knee braces are widely used to treat a variety of knee infirmities. Such braces may be configured to impart forces or leverage on the limbs surrounding the knee joint in order to relieve compressive forces within a portion of the knee joint, or to reduce the load on that portion of the knee. Moreover, in the event that knee ligaments are weak and infirm, a knee brace may stabilize, protect, support, unload, and/or rehabilitate the knee.
The knee is acknowledged as one of the weakest joints in the body, aid serves as the articulating joint between the thigh and calf muscle groups. The knee is held together primarily by small but powerful ligaments. Knee instability arising out of cartilage damage, ligament strain and other causes is relatively commonplace since the knee joint is subjected to significant loads during the course of almost any kind of physical activity requiring the use of the legs.
A healthy knee has an even distribution of pressure in both the medial and lateral compartments of the knee. It is normal for a person with a healthy knee to place a varus moment on the knee when standing so that the pressure between the medial and lateral compartments is uneven but still natural.
One type of knee infirmity that many individuals are prone to having is compartmental osteoarthritis. Compartmental osteoarthritis may arise when there is a persistent uneven distribution of pressure in one of the medial and lateral compartments of the knee. Compartmental osteoarthritis can be caused by injury, obesity, misalignment of the knee, or simply due to aging of the knee.
A major problem resulting from osteoarthritis of the knee is that the smooth cartilage lining the inside of the knee wears away. This leads to a narrowing of the joint space with the development of cysts and erosions in the bone ends. Because of the narrowing of the joint, bone comes directly in contact with bone, and an uneven distribution of pressure develops across the knee which may result in the formation of bone spurs around the joint. All of these changes ultimately lead to increasing pain and stiffness of the joint.
While there are no cures to osteoarthritis, there are many treatments. Individuals who have a diagnosis of isolated medial or lateral compartmental osteoarthritis of the knee are confronted with a variety of treatment options such as medications, surgery, and nonsurgical interventions. Nonsurgical interventions include the use of canes, lateral shoe wedges, and knee bracing.
Knee bracing is useful to provide compartmental pain relief by reducing the load on the affected compartment through the application of an opposing external valgus or varus moment about the knee joint. Unloading knee braces have been shown to significantly reduce osteoarthritis knee pain while improving knee function. Typically, however, the amount of varus and/or valgus rotation that a brace may provide is limited by the use of rigid or substantially rigid supporting struts or frames. While some brace designs do allow for selective, fixed adjustment of the amount of varus and/or valgus rotation provided by the brace, the disclosed embodiments provide an unexpected result of freely adjusting varus and/or valgus rotation for a brace while utilizing the geometry of the leg and the straps of the brace to selectively adjust the varus and/or valgus rotation of the leg for a desired effect.
While known knee braces are successful at reducing pain or at stabilizing a knee joint, many users find these braces to be bulky, difficult to don, complicated to configure, and uncomfortable to wear. For these reasons, the embodiments described herein have streamlined features capable of providing relief for medial or lateral compartmental osteoarthritis, or functional stability of the knee while providing a configuration that has a low profile and unexpectedly provides a more conforming and supportive fit for the orthopedic device.